rapid camshaft wear

Steve121 · Jul 11th, 2006, 08:30

Hi,
Has anyone experienced very rapid camshaft wear in a B18 engine? I'm about to check this in mine because the car doesn't go as well as it did immediately following the engine rebuild (only about 4000 miles ago) Have just had the car rolling road tuned which improved things quite a bit, though the power output is just about standard for a twin SU motor despite the K cam, flowed head, sports exhaust, recurved dizzy (which by itself added 5bhp) and electronic ignition! So I can't think what else would cause the low power. The 'K' cam I have isn't a genuine volvo one, it was 50pounds from Brookhouse Volvo.

Currently putting out a shade under 100bhp at the crank, 83.5 at the wheels.

Amazon Cars' have a very similar spec'd motor which has 125+ bhp!!

My first amazon had a horribly worn camshaft.. between 1 and 2mm lift on each lobe compared to 10.8mm, though it was like this when I bought the car so don't know the period of time this took to wear to such a state.

Andrew (UK) · Jul 11th, 2006, 21:38

I've heard of it but also different opinions on why it happens.
1) Getting lifters upside down or not using new lifters with new cam.
2) Letting the engine idle when first starting after re-assembly
3) Insufficient assembly lube
4) Poorly hardened cam shaft

HTH,
Andrew

Alec Dawe · Jul 12th, 2006, 12:33

If it is the cam worn, I'd go for option 4, poor hardening on the cam lobes, the same malady that used to afflict so many Ford Pinto engines in the '70's

This was usually accompanied by a distinct 'tappetty' noise as well, though.

Steve121 · Jul 12th, 2006, 12:52

The car currently lives at the parent's house as I'm working in France at the mo, so me Dad's gonna measure the lift on the cam, I'm sort of hoping it is a worn cam so at least I know how to fix it!
Was in touch with Rob from Amazon Cars, and he doesn't trust the accuracy of rolling roads as their 122 had 128bhp on one rolling road, and 97 on another... weird!

classicswede · Jul 12th, 2006, 20:03

Could be any of the mentioned resons.

Just for info original cams in 1973 built b20's had bad wear problmes. Normaly noticable at about 90-100,000 miles.

Jul 11th, 2006, 08:30	#1
Steve121 complete member Last Online: Apr 25th, 2024 13:56 Join Date: Dec 2004 Location: Wootton, Bedfordshire	rapid camshaft wear Hi, Has anyone experienced very rapid camshaft wear in a B18 engine? I'm about to check this in mine because the car doesn't go as well as it did immediately following the engine rebuild (only about 4000 miles ago) Have just had the car rolling road tuned which improved things quite a bit, though the power output is just about standard for a twin SU motor despite the K cam, flowed head, sports exhaust, recurved dizzy (which by itself added 5bhp) and electronic ignition! So I can't think what else would cause the low power. The 'K' cam I have isn't a genuine volvo one, it was 50pounds from Brookhouse Volvo. Currently putting out a shade under 100bhp at the crank, 83.5 at the wheels. Amazon Cars' have a very similar spec'd motor which has 125+ bhp!! My first amazon had a horribly worn camshaft.. between 1 and 2mm lift on each lobe compared to 10.8mm, though it was like this when I bought the car so don't know the period of time this took to wear to such a state.

Jul 12th, 2006, 12:33	#3
Alec Dawe Former Support Team Last Online: Jan 26th, 2024 11:26 Join Date: Jan 2006 Location: Nr Norwich	If it is the cam worn, I'd go for option 4, poor hardening on the cam lobes, the same malady that used to afflict so many Ford Pinto engines in the '70's This was usually accompanied by a distinct 'tappetty' noise as well, though. __________________ Alec. (My other car is a WD 2-10-0)

Jul 12th, 2006, 20:03	#5
classicswede Trader Volvo in my veins Last Online: Today 00:50 Join Date: Dec 2004 Location: Anglesey	Could be any of the mentioned resons. Just for info original cams in 1973 built b20's had bad wear problmes. Normaly noticable at about 90-100,000 miles. __________________ http://www.classicswede.org www.classicswede.co.uk

Jul 11th, 2006, 21:38	#2
Andrew (UK) VOC Member Last Online: Dec 3rd, 2021 08:39 Join Date: Jan 1970 Location: Sutton, near Ely	I've heard of it but also different opinions on why it happens. 1) Getting lifters upside down or not using new lifters with new cam. 2) Letting the engine idle when first starting after re-assembly 3) Insufficient assembly lube 4) Poorly hardened cam shaft HTH, Andrew

Jul 12th, 2006, 12:52	#4
Steve121 complete member Last Online: Apr 25th, 2024 13:56 Join Date: Dec 2004 Location: Wootton, Bedfordshire	The car currently lives at the parent's house as I'm working in France at the mo, so me Dad's gonna measure the lift on the cam, I'm sort of hoping it is a worn cam so at least I know how to fix it! Was in touch with Rob from Amazon Cars, and he doesn't trust the accuracy of rolling roads as their 122 had 128bhp on one rolling road, and 97 on another... weird!

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